Hello, I've got a little BP cnc here at my house, and I'm slowly getting better at cutting parts with it. Right now- i'm at the point where my parts are extremely shiney (in alu) and all chamfered, face milled, etc...

I want to know how long it typically takes via rotary or vibratory to go from extremely shiny with slightly visible tool marks (can see but not feel at all), to a decent polish?

I think I have a rotary tumbler lined up for almost free, so I'm thinking about giving that a shot, or I was thinking about either building a vibe tumbler or just buying one.

Soooo, whats a typical cycle time? Could I do this using only one media?

Right now I have no "need" to have polished parts, I just think it'd be a really nice finishing touch, and as an option or something maybe make me a few extra bucks per part.

a tummbler is used to deburr parts as well as prep the surface to accept coatings ,you will not get polished finishes with a tummbler , the media that you use depends greatly on what material you need tumbled , eg if you tumble aluminum with media meant for general steel products ,you can plan to remachine some new parts to replace the ones you ve just destroyed ,
you need to keep in mind that if you are tumbling parts to remove the machining marks , there is a very high chance that the edges could be rounded before it removes the machining marks especially on aluminum ,
one time i forgot aluminum parts in the tumbler for more than eight hours , took em straight to the bin ,they were extremly rounded on edges that were supposed to be slightly deburred
they are deburring machines not polishers

if you want a real shine get a buffing wheel for a bench grinder and some eagle-one aluminum wheel polish
you ll have a mirror finish
after posting ,i did a web search on media, i hate to be misleading ,and it does look as though there is a good amount of media for polishing ,
a friend was telling me a while back that he needed a tummbler or vibrator, and it got me to thinking how easy it would be to build one , i was thinking about cutting a plasic barrel up its sides , laying it down suspended by bunggy cords ,mounting a motor on the bottom and drilling an offset hole in some round stock and bolt it to the motor shaft (like a cam) if the motor runs at a high rpm it should shake the L out of it , the only thing that i see as a future problem would be the motor bearings taking a beating , but i think it would work quite well for a good while before that happened

Exactly was I was going to do with a small plastic water jug... I just have a feeling the polishing media is going to take forever. Thing is, most of my parts at this point at least are extremely small- buffing them with a wheel on a grinder would probably be mostly buffing my hands haha.

Not sure I really want to sling compound all over the shop just yet either.

If the motor bearings don't hold up- You can do as unibiker did and use a jack shaft / belt so that the load is on some large bearings. I looked quite carefully at some commercial ones- it seems the small ones which look like a flying saucer mostly hvae the weight on the motor directly underneath. The really large ones which have a bin and usually weigh 300+ lbs I think I spied the jackshaft and stuff underneath.

Would a Concrete vibrator such as a vibrator from Harbor Freight work to drive a tumbler for deburring?
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=41053

3/4 HP HEAVY DUTY CONCRETE VIBRATOR

Heavy duty unit with a longer, wider shaft than other vibrators. A must for construction, patching and other repair jobs. Concrete vibrator levels and removes air bubbles from concrete. Chrome plated steel connection for vibrator and shaft.
110V, 600 watts
Vibrating rod/head: 2'' dia. x 18''L
Flexible shaft: 1-1/2'' dia. x 26''L



ITEM 41053-6VGA

A bit off topic, but I happen to like the looks (of some) of the machining marks especially in pockets that would be very time consuming to polish. What I don't like is the way Mastercam moves the tool across the bottom of the pocket when it goes to a wall, so I edit the program to raise and lower the tool at that point(s).
By the way, you might be surprised how little time and effort it takes to polish aluminum with a bench grinder with a buffing wheel or wheels and a variety of compounds. Yup, it can be messy.